A court in India has sentenced seven men to death for the brutal rape and murder in February of a Nepalese woman.

The 28-year-old victim was suffering from depression and had been undergoing treatment when she went missing in the northern Haryana state.

Her body was found in a field, three days later. An autopsy revealed that she was gang-raped and had stones, blades and sticks forced inside her.

The female judge said she wanted to send a strong message to the public.

"I award the death sentence to all these accused in the case, and they should be hanged till death," said Judge Seema Singhal, according to the Hindustan Times.

"Besides a judicial officer, I am also a human being and can hear the groan of the victim," Judge Singhal added.

"Women are still facing crime and discrimination from males in our society and we still see gender bias in our system, but the judgement should send a strong message to the people and that is the need of the hour."

An eighth accused attacker, a minor, is being tried in a juvenile court. A ninth suspect killed himself soon after his arrest.

The victim had travelled to Rohtak in Haryana state a few months before the attack, to live with her sister while she underwent treatment for depression at a local hospital.

The doctor who carried out the post mortem examination told Indian media at the time he had "never seen such a horrific case" in his 29-year-long career.

The death sentences came on the same day that India's top court rejected an appeal against the release of the youngest attacker in a fatal gang-rape of a student in New Delhi in 2012.

The savage attack on Jyoti Singh, who was travelling on a bus with a male friend, sparked a huge public outcry in India. The youngest of her attackers was sentenced to three years - the maximum allowed for a minor under Indian law - and released on Sunday.

Singh's mother Asha, who revealed her daughter's name, led protests over the weekend against the man's release.

Scrutiny of sexual violence in India has grown since the Delhi bus attack and the outrage that followed prompted the government to tighten the law.

But experts say tougher laws have failed to bring down the number of rape cases and a series of high-profile crimes have taken place since.